Angioplasty catheters and stents are used in catheter-based procedures to open up a blocked vessel and restore blood flow. In general, physicians use separate devices to perform a single procedure. That is, when treating a vascular stenosis, separate devices/tools are used for embolic protection, stent deployment and post-dilation of the stent. The use of multiple devices to complete a single procedure has many drawbacks. For example, exchanging devices leads to longer procedure time, which poses patient safety risks; manipulation of multiple devices poses potential clinical risk; and interaction between multiple devices poses a risk of device failure. Thus, it is necessary for the surgeon to be trained on multiple devices, and there are higher costs to use multiple devices separately.
More specifically, when treating vascular lesions within the carotid arteries, there is a known risk of embolic material being liberated from the site of treatment during stent deployment or post-deployment balloon dilation of the stent. These embolic particles increase the risk of stroke. To address this risk, many types of vascular embolic filters have been designed. These filters are positioned within the artery past the lesion to be treated and remain in place during the entire procedure. To ensure adequate flow of blood during this time, the filter need to have large pores (100 microns or greater) and are thus only capable of capturing the biggest embolic particles. However, clinical research has shown that smaller diameter embolic particles can also cause stroke. Filter designed to capture small particles can only be left open for a short period. Thus, there is a need for a system that combines multiple products (embolic filter, stent and angioplasty balloon) into a single system that also allows for an embolic filter with small diameter pores (40 microns) to be used ensuring greater capture of embolic material.
In addition, stents are frequently used in conjunction with angioplasty devices in the treatment of vascular narrowing. Carotid stents, as well as stents used in other arterial and venous applications, need to provide sufficient radial strength to keep calcified lesions open and provide sufficient flexibility to travel through and conform to tortuous vessels. In addition, a low area between stent struts is needed to prevent plaque from embolizing through the stent and into the distal vasculature.
Accordingly, a need in the art exists for a treatment device that combines multiple tools needed to treat vascular stenosis into a single device.